Tubular casing



G. C. BURD TUBULAR GAAsING Feb. 7, 1933.

Filed March 25, 1930 INVENTOR. 60E/wmv Cf 50kg \A TTORNEY Patented Feb.7, 1933 UNITI-:D ,STATE-s PATENT oFr-ic GORMAN C. BURD, OF ADRIAN,MICHIGAN, ASSIGNOB TO AMERICAN CABLE COMPANY,

' i INC., A CORPORATION OF DELAWARE Y l 'ruBULAn casina Applicationfiled` March 25, 1930. Serial No. 438,917.

The present invention relates to tubular casings of the type that arebuilt up of hehcally wound metal wires, using the latter term in itsgeneric sense to include strips of various cross-sections, and thegeneral object of the invention is to provide a conduit of the abovetype which will be proof against leakage of lubricant or'other liquid orplastic materials.

The present invention is of particular utility when embodied in theconstruction of flexible casings to receive the operatmg cables forautomobile brakes which must be installed in a manner that permitspivotal movement of the Wheels in steering. To reduce friction with thecable in the casing, it is desirable to fill the latter with a lubricantand it is an object of the present invention to provide means forpreventing escape of of the casing.

Another object of the invention is to provide' means for preventingleakage between the body of the casing and fittings applied thereon.Other objects and advantages of my invention will appear in thefollowing description of a preferred embodiment an thereafter thenovelty and scope of the invention will be pointed out in the claims.

In the accompanying drawing;

Figure 1 is'a side view of a brake cable and casing with certain partsbroken away and other parts shown in section; and

Figure 2 is a view in cross-section and on an enlarged scale, thesection being taken on the line 2 2 of Fig. 1, after the dtting at thatpoint has been subjected to a vswaging rocess. f y

The tubular-casing shown in the drawing comprises an envelope composedof a multiplicity of longitudinally disposed wires 10` laid helicallyand with a relatively long itch. This envelope is mounted between aninner support 11 and an outer support or retainer 12. The inner supportconsists of` a helially coiled wire which is wound withl a slightspacing between the coils. The outer support is also composed of aspirally coiled wire, but with the coils thereof .widely spaced apart.

the lubricant from between component parts The casing is provided oneach end'with a corrugated bushing 13 fitted `gthereon. The bushing isspirally corrugated vso as to fit over and between the coils ofthesupport 12. Fitted tightly over the bushing 13 at one end 55 of thecasing is a fitting 14 and similarly at the opposite end of the casing-afitting 15 is fitted tightly over the bushing 13. These fittings areadapted to be swag'ed on the casin so as to `loe permanently Isecuredthereto and' 60 to press the bushings lfifntfo engagement with theVVenvelop 10., In thertwords, the r/ coill 12 is not sol'ly relied upontothold the fitting on the casing. Thebushings 13 are preferably formed:of" two semitcylinldrical s -ctions Gaps 13a` separate the bushingfsections when they are applied, but? after ,swagingg these gaps aretightly closed, indicated in Fig. 2. 1 i i i 'Passing through the casingand the t o 70 fittings isa brake operating cable 16 whi h is providedat one end with a lfitting 17 a d at the other end' with a `fitting 18.

'The casing is adapted to be filled wi h grease and in forcing thegrease into t e casing there would be a tendency for it .i0 ooze outbetwee the wires of the envelo e 10. To prevent this Iprovid'e cords 19,pf cotton orother suitable material which are laid against the innerwall of the lenvelope in the depressions formed between the wires 10.The cords are held in place by the inner supporting coil 11 and serveasa packing to calk the joints between thewires and to hold the greasein the envelope.` There is also a tendency for the grease to How outbetween the bushing 13 and the outer wall of envelope 10. When the,ifittings are swaged the bushing 13 is pressedfinto close engagementwith the envelope 10, but it is impossible to obtain so tight a lfitthatthere will not be ahelical opening'running along the coils 12 throughwhich the` grease may be forced. To prevent such leakage, I provide ateach end of the casing a cord 20 which is wound about the casing betweenthe coils of the inner support 12. This provides a packing which closesthe helical opening between the bushing and the envelope 10. f f

Having thus described my invention, what 10 I claim as new and desire tosecure by Letters Patent is as follows:

1. A tubular casing formed exteriolfly with a helical rib, a sleevefitted upon one end of .the casing, and a flexible packme within saidsleeve and solely between the coils of the rib te calk the joint betweensaid sleeve andthe casing.

2. A tubular casing formed exteriorly with a helical rib, a bushingfitted on one end of the casing over the helical rib, a flexible packlngwithin the bushing and between the coils 'of the rib, and a memberhaving a socket portion in which the bushingis fixed.

3. A tubular casing comprisng an envelope formed exterioi'ly with ahelical rib, a bushin on one end of the easing, said bushing bemghelically corrugated to fit over and between the coils of the rib, aflexible packing adapted to calk the joint between the bushing and theenvelope, and a member having a socket portion in which the bushing issecured. l

4. A tubular casing formed exteriorly with a helical rib, a sleevefitted upon one end of the casing, and a flexible packing within saidsleeve and between the coils of the rib, said packing extending throughmore than one full turn of the rib to caulk the joint between saidsleeve and the casing.

5. A tubular casing formed exteriorly with a helical rib, a sleevefitted upon one end of the casing, and-a flexible packing in the form ofa cord wound about the casing within the sleeve and between the coils ofthe rib to caulk the joint between said sleeve and the casing.

In testimony whereof, I have signed this specification.

' GORMAN C. BURD.

